What is a successful test case?

Successful test case is one who finds an un-discovered error in the application; test cases are designed having different methodologies like (boundary value analysis, Cause effecting graph, or equivalence partition). Writing test cases which are un-able to cover maximum part of code and obviously have the probability of finding very minimum errors puts question mark in the effectiveness of test cases.In an organization, development managers use the term “successful test case “ in a different way, it is observed if after executing 50 test cases, 35 test cases find errors in the application while execution, the managers used to say the 35 test cases are not successful and 15 are successful J.But as we said the test case that finds error in the application is a successful has proven to be a valuable investment and test cases which do not find any error in the application, because designing test cases is a costly activity.

I have been in software industry for almost 8 years, I got the opportunity of developing web/desktop applications in start of my career mainly based on Microsoft framework,I have also worked in Enterprise Business applications in Micrsoft biztalk server , I have keen interest in the field of Software quality and automation.I enjoy Session based testing/Explorator testing a lot.
I believe that software quality is one of the integral part of the software development, that demands good coding practices, timely reviews and verification right from the beginning. One can not 'paint' quality over the product after its development.